The inside of a MacBook charger

This is one of the older MacBook chargers with the T-shaped MagSafe plug. The collar on the plug is too short, and it frayed and stopped working.

I smashed it open with a hammer.

I didn’t realize it has this whole complex circuit board. I thought power regulation was done mechanically through resistors, then the calculations done by the device receiving power. Makes sense now that I see it, though.Everything is really firmly attached to the board. Aside from the T-plug, the build quality is pretty impressive. Took a lot of prying to get it apart. I guess that’s the reason why it’s so expensive. A million dollars worth of copper. That’s the going rate for copper, right? Millions of dollars per gram? I don’t know. Anyone know what that thing is in the picture above? Resistor, sure, but it looks different from the resistors in the picture below. Those ones are familiar from science class.

Update: It’s a capacitor. Also potentially dangerous, as they store electricity long after they are unplugged. Enough to kill you, maybe.